Remember that patent troll that won that $368 million lawsuit against Apple? VirnetX.
Don’t forget the name, because you may be hearing it a few more times in the near future. They have filed a new lawsuit targeting Apple’s new line of iOS devices, such as the iPhone 5, the Thunderbolt iPad, the iPad mini and the new Macs.
There is a lot to these sorts of things, and many of them have to deal with the US patent system being far from perfect. However, there is a more thorough explanation in the filing.